Influence of manure application method on gray forest soil fertility, crop yield and quality

The article presents the results of field experiments on deepening the arable horizon of gray forest medium loamy soil to increase its fertility through applying organic fertilizer under PY-3-35 layer plow to a depth of 25…27 cm. Low mineralization of organic fertilizer during layer cultivation under oxygen deficiency conditions contributed to accumulation of humus in soil by 6.6 t/ha more than during conventional plowing, and by 7.5 t/ha - than during disking. It also improved water-physical and biological properties of soil: number of water-resistant aggregates increased by 4.6 and 5.3 %, soil density lowered by 0.03 and 0.04 g/cm3, number of earthworms increased by 3...6 individuals, expanded reproduction of fertility was provided, productivity of arable land increased by 7.0 and 6.7 % and crop quality increased compared to conventional plowing and disking, respectively. Deep manure incorporation extended life of organic fertilizer up to 5 years, while after conventional plowing and disking this process lasted only 2...3 years. It is not economically and environmentally beneficial, since frequent application requires a lot of fuel, and a large amount of harmful chemical compounds contained in combustion products is dumped into the environment.